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Leave-in Conditioner

Where you see it: Sprays, Creams, Oils, Mists.

What it is: Leave-in conditioners are at the opposite end of the spectrum as deep conditioning treatments. While the real differences between the two are scientific (the molecules in leave-in conditioners are less prone to crystallizing and are therefore much thinner than those in thick conditioners), a very obvious one is that leave-in conditioners provide a light layer of moisture over the hair. As the title suggests, leave-in conditioners do not have to be washed out.

What it does: Leave-ins should be purchased with a great deal of consideration, because they will stay in your hair until the next rinse — which, if you’re a good girl, won’t be for at least 36 hours. With that said, there are a few commonly used ingredients you should know about to make the best decision for your hair:

• SPF something. Your hair is just as important as your skin, so you should never walk out the door without some sunscreen on! Leave-in conditioners are a great way to give your hair some extra sun protection. (P.S. Blocking sun damage will help prolong that next appointment with your hair colorist.)
• Glycerin. While most in-shower conditioners are dense and rely on oils to hydrate the hair, leave-in conditioners generally avoid oil in favor of glycerin, an ingredient that provides light moisture to your hair without weighing it down (like oils do).
• Oil. Those looking to pump up the moisture more than the volume might find leave-in conditioners with oil as a new best friend. A shiny new best friend, for sure, especially if you’re dealing with frizz.
• Fragrance. Leave-in conditioners are meant to be left in, so make sure you love the scent just as much as you love all of the ingredients, because it will be hanging out with you until the next rinse as well. Though some products do come fragrance-free, a leave-in can be the perfect opportunity to give your hair a scentual (yes, I know that’s not a real word) identity too.

Photo collage featuring products from VO5, L’Oreal, Mixed Chicks, Aussie, Carol’s Daughter